1. Field of the Invention
The present invention relates to a composition and a process for producing a coating for components of a turbomachine having antifouling properties and also to a corresponding coating and a component of a turbomachine coated therewith.
2. Discussion of Background Information
In turbomachines such as stationary gas turbines or aircraft engines ambient air is sucked in and burnt together with the fuel in the combustion chamber in order to be ejected as combustion gases. When the ambient air is sucked in, impurities present in the air, for example sand, soot particles, salt and the like, also get into the turbomachine, where they can lead to deposits on engine components, which can lead to damage to the engine components and/or to impairment of the efficiency of the turbomachine by alteration of the surface quality of the components of the turbomachine by means of the deposits. Particularly in the case of aircraft engines which are operated in different environments, the deposition of impurities sucked in with the ambient air represents a serious problem.
To counter this problem of formation of deposits, which is also referred to as “fouling”, attempts have been made in the past to provide the surfaces of components with coatings which have antifouling properties, as are described, for example, in DE 196 06 011 A1, EP 0 885 938 A2, U.S. Pat. No. 6,159,547 A, WO 2008/132196 A1 or GB 2 428 604 A, the entire disclosures of which are incorporated by reference herein.
However, the known antifouling layers either display unsatisfactory antifouling properties, especially when used in aircraft engines, or are unsuitable for the expected or desired environmental conditions in turbomachines. In addition, there is the problem that antifouling layers frequently contain Cr(VI) compounds which owing to their health-endangering properties and the processing difficulties resulting from the high safety requirements are not practicable to use.
In view of the foregoing, it would be advantages to have available a coating which provides antifouling properties for components of turbomachines. The corresponding coating should be reliable to use under the ambient conditions of a turbomachine and make safe and uncomplicated production, processing and use possible.